Is your furniture gray or navy? hard to tell from the glare in the pictures.

I feel like ( realize someone put lights there) your bed might be better somewhere else, ....

I feel like the room needs a pretty big rug, I’d be tempted to pick out a nice broadloom and have it cut and edged to size, it’s very economical - plus large matching lamps for the bedside tables and i would add a big happy live tree by the window

Furniture is Gray and there's brass in the lights and knobs

If you're just going to have a white duvet you have quite a lot of latitude when choosing a rug. If there is a carpet store nearby, first look at their remnants to see if any of those appeal as they would be the least expensive option, then move on to their stock carpet, and then special order material for which they have sample boards. If you like color and/or pattern you can make a statement with the rug since everything else in the room so far is plain. It looks like you might have room for a chair next to the low double dresser. Measure the space, and if you think you would use a chair, look for one in an appropriate size. Or maybe a chaise would fit.

Define your color scheme/design based on headboard.

Suggest a natural fibre rug as a calm backdrop, vs rug taking over room. It will also open up more decor/accessories choices.

Rug should be wide enough for nightstands to feel balanced and it can be under them or a bit lower.

Bedding is so important and add a tapered bedskirt as well.

Consider removing the sconces and repairing wall as they are oddly placed. Add matching lamps on the nightstands and even add curtains to balance that wall.

Under the window, lots of options and if you think you would relax there, some ideas below.

Look for rugs labeled "faded vintage," "neutral oriental," or "distressed traditional" in 12x15.

Brands like Loloi, Surya, or Safavieh have large sizes in these palettes.

As for under the windows space-

there are some options

1.Bench Seating

Place a long upholstered bench or wood bench under the windows.

Add a few throw pillows to make it feel styled but not cluttered.

This keeps the space open but still functional (great for extra seating)

2. Console table

A narrow wood console under the windows can act as a decorative piece without blocking light.

Style with plants, stacked books, or a ceramic vase to tie in with the natural view outside.

This option is clean and polished, perfect if you want less “lounging furniture” in the bedroom.

or if you want to go minimalist then nothing, just use drapes and may be some plants in baskets.